It is known in the art to which this invention relates that a monofilament or continuous fiber refers to one single fiber. Several continuous fibers when taken together are considered as a strand, and if cut to discrete lengths of staple fibers, become chopped strand from which a chopped strand mat can be made. A plurality of continuous filaments can also be referred to as yarns, especially if some twist of the individual filaments is involved. Yarns generally have reference to the textile industry. Also, if a plurality of continuous filaments are considered, in which the filaments are generally parallel to one another then those filaments are collectively referred to as rovings.
With that introductory explanation, it will be recognized in this art that staple fibers of glass, for instance, can be produced in strands, cut to a discrete length and formed into a chopped strand mat structure to which a binder or sizing agent can be applied, if necessary. This chopped strand mat structure can then have a resinous material added to it when it has been placed in a mold, with the chopped strand mat structure thus being "wetted out" i.e., having the chopped strands coated with some of the resin. Following heating and curing of the resin coated mat structure, an article can be produced as a sheet, a shell or any other form. Such an article can then be used, for example, in the transportation, construction or other related industries where glass reinforced plastics in the form of panels, or other molded parts are frequently used. At present, those industries in which a matrix material is to be reinforced most frequently make use of a chopped strand mat structure that is made from a roving. Since a strand from which such a chopped strand mat structure is made generally consists of hundreds of filaments, the resulting mat structure is relatively coarse. As a result, significant difficulties are encountered, for instance, in using such a chopped strand mat structure in connection with coating or "wetting out" the chopped strands and staple fibers with a matrix material, uniformly, so as to provide a homogeneous distribution of the glass fibers in the resulting structure. This matrix material could be a polyester, an epoxy, a phenol or other such resinous material. In other words, difficulties have previously been encountered in achieving a glass load uniformly within the matrix material. In one of the processes currently being used to produce rolled chopped strand matting for the glass reinforced plastics industry, a relatively large number of operating personnel are required to perform all of the necessary operations that are involved. Moreover, the equipment can occupy considerable volumes of space and this involves large capital expenditures in building and maintenance costs. Briefly then, prior art processes used for producing a chopped strand mat structure for those industries requiring matrix material to be reinforced, have been subject to certain problems.
It is also well known in the art to which this invention relates that superfine textile filaments have been produced by methods which have not been economically attractive. These superfine filaments are relatively thin, being of the order of about 10/100,000 of an inch in diameter. Consequently, they are rather delicate and fragile, and are prone to breakage when they are physically handled. It is primarily because of the hazard for breakage that accompanies physical contact of the fibers by mechanical equipment, that has resulted in the industry being unable to achieve production which is as economically attractive as one would like.